3.2. The class of a word can often be changed by adding a suffix. For example, if –er is added to the verb scan (and the 'n' is doubled) we get the noun scanner.
Common adjectival suffixes are: -ing, -y, -able, -ible, -ive, -al, -ed, -ful
Common noun suffixes are: -er, -or, -ion, -tion, -ation, -ment, -ness, -ity, -ant,
Put the following words into the correct column below:
Computer, self-calibrating, easy, resolution, sharpness, information, printed, personal, capable, compression, technology, calculator, useful assistant, expensive, possibility, reducible, investment
Adjectives |
Nouns |
|
|
Some words have been left out of this persuasive advertisement. Read it and complete it with words from the box.
Vivid, easy-to-use, faster, fashionable, wide, shots |
If you want great pictures from an (1)…. digital camera, you want the Kodak DC215. Now you can capture life's memories in style with this sleek and (2)…..digital camera. The camera's 2X (29 mm-58 mm) optical zoom lens lets you get close up and personal without sacrificing image detail or quality while the (3)….. angle lens design helps you capture more in each shot. With one million (1152 x 864) pixels, you'll have enough detail to generate crisp, (4)…. realistic photos up to 5" x 7". The 1.8" colour LCD lets you preview and review your pictures so you get only the (5)…. you want, and lets you delete those you don't. With the included USB COMPACTFLASH Card Reader, you can download pictures up to ten times (6)…. than with serial connections for faster image sharing.
Vocabulary
4.1. Make new words with the base words, using the suffixes and/or prefixes. Sometimes you need to make small changes to the spelling.
Prefixes |
Base |
Suffixes |
-un
re- |
add
process
emit
resolve
deep
fresh
speak
scan
|
-ing
-sion
-tion
-th
-ness
-er
-able |
Give derivates to the following words.
to design, to execute, to calculate, to program, to simulate, to test, to decode, to unpack, to print, to install, to operate, to process
Speaking and Writing
5.1. Speak on the main features of the printer you prefer to use. Discuss it with your group-mate. Give reasons.
5.2. Write a brief report from your notes.
Unit 4.
Reading
Computer data processing.
A central processing unit (CPU) or processor is an electronic circuit that can execute computer programs. This term has been in use in the computer industry at least since the early 1960s.
Die
of an Intel 80486DX2 microprocessor in its
packaging.
The fundamental operation of most CPUs, regardless of the physical form they take, is to execute a sequence of stored instructions called a program. The program is represented by a series of numbers that are kept in some kind of computer memory. There are four steps that nearly all CPUs use in their operation: fetch, decode, execute, and writeback.
The first step, fetch, involves retrieving an instruction (which is represented by a number or sequence of numbers) from program memory. The location in program memory is determined by a program counter (PC), which stores a number that identifies the current position in the program. In other words, the program counter keeps track of the CPU's place in the current program. After an instruction is fetched, the PC is incremented by the length of the instruction word in terms of memory units. Often the instruction to be fetched must be retrieved from relatively slow memory, causing the CPU to stall while waiting for the instruction to be returned. This issue is largely addressed in modern processors by caches and pipeline architectures.
The instruction that the CPU fetches from memory is used to determine what the CPU is to do. In the decode step, the instruction is broken up into parts that have significance to other portions of the CPU. The way in which the numerical instruction value is interpreted is defined by the CPU's instruction set architecture (ISA). Often, one group of numbers in the instruction, called the opcode, indicates which operation to perform. The remaining parts of the number usually provide information required for that instruction, such as operands for an addition operation. Such operands may be given as a constant value (called an immediate value), or as a place to locate a value: a register or a memory address, as determined by some addressing mode. In older designs the portions of the CPU responsible for instruction decoding were unchangeable hardware devices. However, in more abstract and complicated CPUs and ISAs, a microprogram is often used to assist in translating instructions into various configuration signals for the CPU. This microprogram is sometimes rewritable so that it can be modified to change the way the CPU decodes instructions even after it has been manufactured.
After the fetch and decode steps, the execute step is performed. During this step, various portions of the CPU are connected so they can perform the desired operation. If, for instance, an addition operation was requested, an arithmetic logic unit (ALU) will be connected to a set of inputs and a set of outputs. The inputs provide the numbers to be added, and the outputs will contain the final sum. The ALU contains the circuitry to perform simple arithmetic and logical operations on the inputs (like addition and bitwise operations). If the addition operation produces a result too large for the CPU to handle, an arithmetic overflow flag in a flags register may also be set.
The final step, writeback, simply "writes back" the results of the execute step to some form of memory. Very often the results are written to some internal CPU register for quick access by subsequent instructions. In other cases results may be written to slower, but cheaper and larger, main memory. Some types of instructions manipulate the program counter rather than directly produce result data. These are generally called "jumps" and facilitate behavior like loops, conditional program execution (through the use of a conditional jump), and functions in programs. Many instructions will also change the state of digits in a "flags" register. These flags can be used to influence how a program behaves, since they often indicate the outcome of various operations. For example, one type of "compare" instruction considers two values and sets a number in the flags register according to which one is greater. This flag could then be used by a later jump instruction to determine program flow.
After the execution of the instruction and write back of the resulting data, the entire process is repeated, with the next instruction cycle normally fetching the next-in-sequence instruction because of the incremented value in the program counter.
Random-access memory (usually known by its acronym, RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order (i.e., at random). The word random thus refers to the fact that any piece of data can be returned in a constant time, regardless of its physical location and whether or not it is related to the previous piece of data.
By contrast, storage devices such as tapes, magnetic discs and optical discs rely on the physical movement of the recording medium or a reading head. In these devices, the movement takes longer than data transfer, and the retrieval time varies based on the physical location of the next item.
The word RAM is often associated with volatile types of memory (such as DRAM memory modules), where the information is lost after the power is switched off. Many other types of memory are RAM, too, including most types of ROM and flash memory called NOR-Flash.
Example
of writable
volatile
random access
memory.
Read-only memory (usually known by its acronym, ROM) is a class of storage media used in computers and other electronic devices. Because data stored in ROM cannot be modified (at least not very quickly or easily), it is mainly used to distribute firmware (software that is very closely tied to specific hardware, and unlikely to require frequent updates).
Transformer
matrix ROM
(TROS), from the IBM System 360/20
In its strictest sense, ROM refers only to mask ROM (the oldest type of solid state ROM), which is fabricated with the desired data permanently stored in it, and thus can never be modified. However, more modern types such as EPROM and flash EEPROM can be erased and re-programmed multiple times; they are still described as "read-only memory"(ROM) because the reprogramming process is generally infrequent, comparatively slow, and often does not permit random access writes to individual memory locations.
Units of memory: Computers represent information in binary code, written as sequences of 0s and 1s. Each 1 or 0 is called a binary digit or bit. Bits are grouped into eight-digit code. Eight bits together are called a byte. In order to avoid complex calculations of bytes, we use bigger units. A kilobyte (KB) is 1,024 bytes; a megabyte (MB) is 1,024 kilobytes; a gigabyte (GB) is 1,024 megabytes; a terabyte (TB) is 1,024 gigabytes. We use these units to describe the RAM memory, the operating capacity and the size of a program or document.